Picture scanning and assembling device for television and picture transmission



1932- F. VON OKOUCSANYI ET AL. 1,387,472

PICTURE SCANNING AND ASSEMBLING DEVICE FOR TELEVISION AND PICTURE TRANSMISSION Filed Sept. 17, 1950 2 Sheets-Sheet 1 [an aa/fcsany/ 9 6 mkk n AQw'er 8, 1932- F. VON OKOLlCSANYi ET AL PICTURE SCANNING AND ASSEMBLING DEVICE FOR TELEVISION AND PICTURE TRANSMISSION Filed Sept. 17, 1930 2 Sheets-Sheet Patented Nov. 8, 1932 1 UNITED STATES PATENT orrlcs FRANZ voN oxomosANYr, or RnRLIN-wInMnRsnoRr, AND eos'rnv WIKKENHAUSER, or RERLIN-HALENSEE, GERMANY, ASSIGNORS T0 TELEHOR AKTIEN-GESELLSGHAFT, or BERLIN-CHARLOTTENBURG,-GERMANY I 1 I PICTURE SCANN NG AND AssEMRLINe DEVICE FOR TELEVISION AND rIo'rURE TRANSMISSION Application filed September 17, 1930, Serial No. 482,612, and in Germany August 5, 1930.

Picture scanning and assembling devices (for instance Nipkow disc, Weillers rotating mirror, or the like) as hitherto known have the disadvantage that when a larger number of picture elements are used their diameter becomes solarge that they can no longer be used in practice. At the same time, the dimensions of the holes in the case of Nipkow discs become so small that they can no longer be made sufliciently accurate.

Assembling devices are also known in which a rotary system comprising a number of mirrors corresponding to the number of picture lines is provided, which mirrors are arranged next to one another along an axis of rotation, being distributed at equal angulardistances from one another over the range of rotation. In these known picture assembling devices a source of light in the form of a point, which is modulated by the photoelectric currents, is projected upon a screen through the intermediary of condensers. Such an arrangement, however, is practicable only when the number of picture lines is small. The arrangement completely fails when the number of lines is increased, since theangles which are enclosed by the individual mirror surfaces then become so small that the beam of light which appears on the reflecting surface with a width several times larger than that of the source of light employed is reflected at thesame time by a number of mirrors, so that a number of points of light appear on the screen, whereby the picture becomes useless.

These drawbacks are avoided according to the present invention by this that sub'ective observation is substituted for the pro1ection and that an elongated or linear source of light is used instead of a point of light, for instance a glow tube which is arranged parallel to the axis of rotation of the mirror system at a suitable distance. therefrom. Moreover, for the subjective observation, it is necessary that the minimum length of the individual mirrors shall be equal to the length of the picture lines.

The invention is illustratedv diagrammatically and by way of example in the accompanying drawings, in which on the picture assembling device.

which consists of two wires 6 and 7 respectively to which the received photoelectric Figure 1 showsin perspective View the essential parts of the television receiving ape paratus for the direct viewing of the picture Figure 2 is a plan view of a television receiving apparatus provided with a device for juxtaposed plates 4a4f, each one of which is provided with a mirror surface 410-42.

The mirror surfacesare displaced relatively to one another through an angle of so that they are uniformly distributed on the periphery of the picture assembling device. The mirror-42 cannot be seen in Figure 1, since it is covered by the parts which lie in front. 'An elongated or linear source of'light '5 is-arranged near the mirror cylinder, the

said source of light being in the present case a glow discharge lamp, the two electrodes of currents are applied. When the phonic wheel 1 runs synchronously with the picturescanning device of the transmitter at such a speed that the mirror cylinder 4 makes one complete revolution of 360 during the period of transmission of each individual picture, the eye 9 of the observer sees when thecylinder 4 rotatesin the direction of the arrow 10 a point of lightrepresenting the corresponding picture element, which point of light runs consecutively on the mirrors 4a-4f from the leftto the right-handside,whereby an assembling of the picture is obtained. The point of light appears as a reflected picture of the section of the glowing tube 5 corresponding to the respective individual mirror and "the intens'ityofits brightness corresponds to the brightness at the particular, moment of the xlight radiated from the glow tube. -Theuse ture cylinder at equal angular distances, that is to say the reflecting surfaces in the case of 30 picture "lines enclose an angle of- In the arrangement illustrated in Fig. 1,

the mirrors have a width which is limited by the width of the picture lines; the length thereof may, however, vary as desired, being above the minimumlength determined by the length of the picture element. Preferably V the length of themirror is made substantially equal to the length of the picture lines, as can be seen from Figure 1.

The adjustment of the phase can be effected in a Very simple manner by this that the mirrors which are arran ed at equal angular distances from one another are provided in a greater number than that corresponding to the number of the picture lines over an angle exceeding 360, that is to say the screw, which is so to say formed by the mirrors, is continued beyond a full revolution. The phase adjustment can then be efiected simply by a displacement of the mirror system in the direction of the axis 'of rotation. f

One arrangement for carrying this idea into effect is illustrated by way of example in Figures 2 and 3, it being assumed that in this case use is made of a picture having 20 picture lines. Accordingly 20 separate mirrors 20 are employed, which are distributed over the normal length 21 of the picture cylinder,

being arranged next to one another at equal angular distances. In order to render possible the phase adjustment, the picture cylinder iscontinued by another picture cylinder of the same construction. Inother words, a similar system of 20 mirrors 22 forms a continulength of the ordinary mirror cylinders.

In front of the mirror cylinder which retended to receive two rollers 27 which are se cured to the ends of the prongs of a forked member 28. The latter member is secured to a screw nut 29 which can be axially displaced on a rotary butaxially fixed screw spindle 30 by the rotation of the latter by means of a crank handle 31 .being secured against rotation by means of a guiding rod 32.

What we claim is i V 1. An apparatus for television reception and the reception of electrically transmitted pictures comprising in combination a linear source of li ht intended to be controlled by the receivec currents and a rotary system of mirrors, the number of which corresponds to the number of the picture lines, the said mirrors being arrangednext to one another along an axis of rotation and distributed at equal angular distances from one another over the range of rotation, the linear source of light being arranged to lie parallel to the said axis of rotation'and to produce its image in the system of mirrors direct without the interposition of any optical system, and w the minimum length of the individual mirrors being equal to the length of the picture lines.

2. A picture assembling device as claimed in claim 1 and in which the individual mirrors which are arranged at equal angular distances from one another are continued be- 'ationof the mirror system 20. Thus the total length of the mirror cylinder is double the ceives its illumination, for instance in the I, manner indicated 1n F lgure 1, there 1s provided a mask 23 corresponding to the picture dimensions. The mirror cylinder is displaceably mounted on the shaft 25 which is driven by the phonic'wheel 24, the displace- -ment being effected axially in each direction to the extent of half the width of the picture. This displacement enables the right phase to be obtained. v

Inorder to effect the displacement'in the arrangement illustrated in the drawings, an annular track 26 'is provided at the end of a the mirror cylinder, the said track being in- 

